Pump



J. H. BROWN June 30, 1931.

PUMP

Filed May 2, 1927 2 Sheets-Sheet 1 1/227! AZ Zrawzz raw.-

Patented June 30, 1931 UNITED s'rras PATENT OFFICE JOHN H. BROWN, OFHOLLYVTOOI), CiLIFGIt-NIEA, ASSIGNOR, BY FIESNE ASSIGNMENTS, TOINSTANT-ICE CORPORATION, A GORI-ORATION OF DELAWARE PUMP Applicationfiled May 2,

The invention relates to refrigerating machines primarily design forhousehold use and has for its object the obtaining of a machine havingthe following advantages over the average machines now in use for thesame purpose. 7

' First; decrease in the cost of manufacture.

Second; increased efficiency.

Third; decrease in the space dimensions required for its installation.

Fourth; lowering the cost of shipment.

Fifth; reduction in weight so that the unit may be handled and installedby a single workman.

Sixth; decrease in cost of operation.

Seventh; freedom from corrosion by the refrigerant.

Eighth; decrease in the cost of repairs.

In the present state of the art ammonia is the refrigerant in mostgeneral use in commercial refrigerating plants and to a very limitedextent in domestic machines. It has been found, however, that in smallmachines there are certain objections to the use of ammonia and as aconsequence other refrigerants such as sulphur dioxide (S0 have comeinto more general use for these small machines. I have discovered thatby certain changes in construction of the machine the diflicultiesencountered in the use of ammonia may be eliminated and thatconsequently its greater efficiency as a refrigerant can be takenadvantage of. I have also discovered that one of the most seriousobjections to the use of ammonia (the suffocating gas evolved when itescapes from the machine) may be avoided by limiting the quantity ofrefrigerant used to very much less than heretofore deemed necessary. Myinvention therefore consists in the general reorganization of themachine and in certain specific features of construction as hereinafterset forth.

In the drawings; I

Figure 1 is a vertical longitudinal section 1927. Serial No. 188,309.

partly in elevation through my improved machine.

Figure 2 is an enlarged section through the upper portion of thecylinder and piston.

Figure 3 is an enlarged section through the chambered housing.

Figure l is an enlarged section through the regulator.

Generally described my improved machine comprises a base A on which ismounted a compressor unit B and an electric motor C for operating thesame. The compressor includes a cylinder D preferably integral with acombined crank and gear case E, also a cylinder head F, a piston G,connecting-rod H and crank shaft 1. The'casing E is divided by apartition E into a crank chamber E and a gear chamber E but thesechambers are in communication with each other through the gas passage Eand oil passage E through the wall E respectively in the upper and lowerportion thereof The crank shaft I-is journaled in bearings in thepartition E, integral end head E and removable end head J.Alignedbushings KJK, K 7 are placed in these several parts to form thejournal bearings and as the end journals do not extend through the headsthere will be no opportunity for escape of the refrigerant gastherethrough. The crank shaft is driven 7 from a parallel shaft Lthrough the medium of a step down gearing M, M arranged in thecompartment E The shaftL is journaled preferably in ball bearings L andpasses outward fromt-he chamber E through a packing gland N this beingpreferably pro vided with an adjustable capN' and spring N tensionedthereby to automatically take up wear and to maintain the seal. Themotor C has its shaft C"substantially aligned as with the shaft L butconnected thereto through a flexible coupling C which compensates forany slight inaccuracy in alignment.

The inlet and outlet valvesfor the compressor are located respectivelyat the upper end of the piston and at the upper end of the cylinder. Theconstruction of these valves is a very important feature of my inventionthrough the use of which I have obtained results not secured by othertypes of valve. Each valve comprises a ported flat seat plate and a discof exceedingly thin and flexible resilient material normally engagingsaid seat. The seat for the inlet vlave is the upper end of the pistonwhich has a circular series of ports covered by the flexible disc Pwhich latter is centrally secured to the piston head by the screw P. Theseat for the outlet valve is formed by a plate Q located in acountersunk recess Q, at the upper end of the cylinder casing andmarginally secured by screws Q This plate Q is also provided with i acircular series of ports 6 normally covered by the flexible disc P whichis centrally apertured to flt a hub Q projecting upward from the plate Qand is secured by a clamping screw Qfl washer Q and spacer Q. The plateQ, on its lower side is centrally recessed to receive the screw P on thepiston so that the piston may take its full stroke with a minimum ofclearance and without interference by the screw with the plate Q.

As has been stated, the discs P and P are formed of very tin andflexible resilient material preferably sheet steel, and I have foundthat a thickness of from six to eight thousandths of an inch is suitablefor the purpose. Due to this flexibility each disc will accurate 1yconform to the face of the seat so that a very slight gaseous pressureoperating thereon is sufficient to maintain a gas tight seal. henhowever. the pressure is reversed and acts upward upon the disc throughthe ports in their seats a flexing and dishing is produced which willsupply a free passage for the gas. The cylinder head F has a portionfitting in the countersunk recess Q, of the cylinder, this portion beingfashioned to provide clearance for the hub Q} and securing screw Q,*.There is also a central gas passage F through the head surrounded by anan nular water passage F The passage It communicates with a passage in asuper head R having a stepped engagement with the head F and thispassage R is laterally connected to the condenser S which extendsdownward therefrom into a chamber within the base A. The condenser S hasa series of parallel loops arranged within the base, the end loop havingan upward extension S located centrally of the base between the motorand the This condenser is preferably formed of an outer conduit whichconveys the refrigerant and an inner conduit S for carrying coolingwater. The conduit S has one end extending laterally through the head Rand having a. loop S connecting it with the annular water passage F Theopposite ends of the concentrically arranged conduits are connected to awater regulator T mounted on a bracket U preferably forming a portion ofa cover U for the gear case E, the construction of the water regulatorbeing as follows:

This housing of the regulator T has a chamber T therein in communicationwith the outer or refrigerant conduit S and forming a storage receptaclefor the liquid refrigerant. One wall of this chamber is formed by theflexible diaphragm T marginally clamped by the cover T on which a leverT is fulcrumed at T. T is a member resting on the diaphragm and havingan upwardly projecting finger engaging a notch T in the lever T adjacentto its fulcrum or pivot T One end of the lever T is connected with atension spring T while the opposite end of the lever is attached to thestem T of a water controlling valve T This valve T controls the passagewith which the water conduit S of the condenser is connected and thearrangement is such that whenever the pressure of the gas in the chamberT reaches a predetermined height the diaphragm T Will be deflectedoutwardly rocking the lever T to open the valve T. On the other handwhen the pressure within the chamber T falls, the tension of the springT will move the lever T in the opposite direction thereby closing thevalve T The construction as thus far described together with a.suit-able expansion or refrigerating coil V and a pressure reducing orexpansion valve W used in connection there with, constitutes thecomplete apparatus. The compressor unit may be located either in acompartment of the refrigerator or in any other convenient location andits dimensions are such that very little space is required; also itstotal weight is such that it can be handled and carried by one man whichreduces the cost of installation and service. The expansion valve may beof any suitable construction but as shown comprises the chamberedhousing V having a flexible diaphragm lV therein engaging the stem of avalve V. controlling the passage of the refrigerant from the highpressure to the low pressure side of the system. The diaphragm W hasafollower resting thereon and under the tension of a spring ll whichtension may be adjusted by a screw VV". Thus the valve may be set tomaintain any predetermined differential pressure between the two sidesof the system.

In charging the apparatus a comparatively small quantity of liquidammonia is introduced and I have found that from three to five ounces issuiiicient when used with an expansion coil of three-eighths inch steeltubing sixty-seven feet in length the compressor having a piston one andone-half inches in diameter and-one and three-quarters inches stroke.Such a small quantity of the refrigerant would not be dangerous even ifthe whole were permitted to escape from the apparatus which would seldomif ever, occur. Thus one great objection to the use of ammonia isovercome.

In connecting the apparatus with the water supply the water is admittedto the conduit S through the condenser coils S in a direc tion which isreverse from the flow of the refrigerant therethrough. This has theeffect of subjecting the coolest portion of the refrigerant to theaction of the coldest water so that a greater reduction in temperatureis obtained than would be the case if the flow of both fluids werein'the same direction. After passing through the condenser coil and intothe water passage F of the head F the water is discharged through anysuitable conduit to the drain. The consumption of water will beproportional to the refrigeration and at times the flow is completelyout off so that there is no needless waste of water.

To guard against accident in case of an abnormal pressure in the systemI preferably provide means for stopping the motor under such condition.As shown diagrammatically an automatically opening electric switch Xcontrolling. the motor circuit is normally lock closed by a catch X andan arm X for releasing said catch extends into the path of the lever TUnder normal operation the lever T will not move far enough to actuatethe arm X but should the pressure in the system rise to an abnormalheight due to failure in cooling or from any other cause this would movethe lever T suficiently to actuate the arm X releasing the catch X andpermitting the switch to automatically open. This would stop the motorand therefore prevent further rise in pressure.

The operation of the machine Will be understood without furtherdescription but in brief is as follows: The expansion coil V having oneend connected with the crank case, the operation of the compressor willcontinuously withdraw ammonia gas from the low pressure side of thesystem compressing and ejecting the same into the high pressure side. Inthis operation the flexible discs P and P will alternately close andopen their respective ports and by reason of the fact that these discsare always attached centrally to their seats and have their marginalportions progressively flexed away from the same, the operation will benoiseless. This is particlarly advantageous where the compressor isinstalled in the refrigerator box where valve noise would be veryobjectionable. Another advantage of the valve construction is thatclearances are reduced to the minimum so that substantially the fullvolume of gas filling the cylinder on the downward stroke of the pistonwill be compressed and ejected through the valves.

hat I claim as my invention is:

In a compressor, the combination of a crank case having a partitiontherein dividing the space enclosed into a crank chamber and a gearchamber, said partition having JOHN H. BROWN.

